[apple/xnu.git] / osfmk / ddb / db_lex.c

/*
 * Copyright (c) 2000-2006 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 * 
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */
/*
 * @OSF_COPYRIGHT@
 */
/*
 * HISTORY
 * 
 * Revision 1.1.1.1  1998/09/22 21:05:48  wsanchez
 * Import of Mac OS X kernel (~semeria)
 *
 * Revision 1.1.1.1  1998/03/07 02:26:09  wsanchez
 * Import of OSF Mach kernel (~mburg)
 *
 * Revision 1.1.11.3  1996/01/09  19:15:49  devrcs
 * 	Change 'register foo' to 'register int foo'.
 * 	[1995/12/01  21:42:12  jfraser]
 *
 * 	Merged '64-bit safe' changes from DEC alpha port.
 * 	[1995/11/21  18:03:11  jfraser]
 *
 * Revision 1.1.11.2  1995/01/06  19:10:21  devrcs
 * 	mk6 CR668 - 1.3b26 merge
 * 	* Revision 1.1.4.6  1994/05/06  18:39:20  tmt
 * 	Merged osc1.3dec/shared with osc1.3b19
 * 	Merge Alpha changes into osc1.312b source code.
 * 	String protos.
 * 	64bit cleanup.
 * 	Cleanup to quiet gcc warnings.
 * 	* End1.3merge
 * 	[1994/11/04  08:49:35  dwm]
 * 
 * Revision 1.1.11.1  1994/09/23  01:19:59  ezf
 * 	change marker to not FREE
 * 	[1994/09/22  21:10:14  ezf]
 * 
 * Revision 1.1.4.4  1993/08/11  20:37:55  elliston
 * 	Add ANSI Prototypes.  CR #9523.
 * 	[1993/08/11  03:33:26  elliston]
 * 
 * Revision 1.1.4.3  1993/07/27  18:27:38  elliston
 * 	Add ANSI prototypes.  CR #9523.
 * 	[1993/07/27  18:12:13  elliston]
 * 
 * Revision 1.1.4.2  1993/06/02  23:11:27  jeffc
 * 	Added to OSF/1 R1.3 from NMK15.0.
 * 	[1993/06/02  20:56:32  jeffc]
 * 
 * Revision 1.1  1992/09/30  02:01:10  robert
 * 	Initial revision
 * 
 * $EndLog$
 */
/* CMU_HIST */
/*
 * Revision 2.5  91/10/09  16:00:20  af
 * 	 Revision 2.4.3.1  91/10/05  13:06:25  jeffreyh
 * 	 	Added relational operator tokens and string constant etc.
 * 	 	Added input switching functions for macro and conditional command.
 * 	 	Moved skip_to_eol() from db_command.c and added db_last_lp to print
 * 	 	  skipped input data as a warning message.
 * 	 	Added last input repetition support to db_read_line.
 * 	 	Changed db_lex() to always set db_tok_string for error message.
 * 	 	[91/08/29            tak]
 * 
 * Revision 2.4.3.1  91/10/05  13:06:25  jeffreyh
 * 	Added relational operator tokens and string constant etc.
 * 	Added input switching functions for macro and conditional command.
 * 	Moved skip_to_eol() from db_command.c and added db_last_lp to print
 * 	  skipped input data as a warning message.
 * 	Added last input repetition support to db_read_line.
 * 	Changed db_lex() to always set db_tok_string for error message.
 * 	[91/08/29            tak]
 * 
 * Revision 2.4  91/05/14  15:34:23  mrt
 * 	Correcting copyright
 *
 * Revision 2.3  91/02/05  17:06:36  mrt
 * 	Changed to new Mach copyright
 * 	[91/01/31  16:18:20  mrt]
 * 
 * Revision 2.2  90/08/27  21:51:10  dbg
 * 	Add 'dotdot' token.
 * 	[90/08/22            dbg]
 * 
 * 	Allow backslash to quote any character into an identifier.
 * 	Allow colon in identifier for symbol table qualification.
 * 	[90/08/16            dbg]
 * 	Reduce lint.
 * 	[90/08/07            dbg]
 * 	Created.
 * 	[90/07/25            dbg]
 * 
 */
/* CMU_ENDHIST */
/* 
 * Mach Operating System
 * Copyright (c) 1991,1990 Carnegie Mellon University
 * All Rights Reserved.
 * 
 * Permission to use, copy, modify and distribute this software and its
 * documentation is hereby granted, provided that both the copyright
 * notice and this permission notice appear in all copies of the
 * software, derivative works or modified versions, and any portions
 * thereof, and that both notices appear in supporting documentation.
 * 
 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 * 
 * Carnegie Mellon requests users of this software to return to
 * 
 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
 *  School of Computer Science
 *  Carnegie Mellon University
 *  Pittsburgh PA 15213-3890
 * 
 * any improvements or extensions that they make and grant Carnegie Mellon
 * the rights to redistribute these changes.
 */
/*
 */
/*
 *	Author: David B. Golub, Carnegie Mellon University
 *	Date:	7/90
 */
/*
 * Lexical analyzer.
 */
#include <string.h>			/* For strlcpy(), strlcmp(), strlen() */
#include <ddb/db_lex.h>
#include <ddb/db_command.h>
#include <ddb/db_input.h>
#include <ddb/db_output.h>		/* For db_printf() */

char	db_line[DB_LEX_LINE_SIZE];
char	db_last_line[DB_LEX_LINE_SIZE];
const char *db_lp, *db_endlp;
const char *db_last_lp;
int	db_look_char = 0;
db_expr_t db_look_token = 0;


/* Prototypes for functions local to this file.  XXX -- should be static!
 */
void db_flush_line(void);
void db_unread_char(int c);


int
db_read_line(const char *repeat_last)
{
	int	i;

	i = db_readline(db_line, sizeof(db_line));
	if (i == 0)
	    return (0);	/* EOI */
	if (repeat_last) {
	    if (strncmp(db_line, repeat_last, strlen(repeat_last)) == 0) {
		strlcpy(db_line, db_last_line, DB_LEX_LINE_SIZE);
		db_printf("%s", db_line);
		i = strlen(db_line);
	    } else if (db_line[0] != '\n' && db_line[0] != 0)
		strlcpy(db_last_line, db_line, DB_LEX_LINE_SIZE);
	}
	db_lp = db_line;
	db_endlp = db_lp + i;
	db_last_lp = db_lp;
	db_look_char = 0;
	db_look_token = 0;
	return (i);
}

void
db_flush_line(void)
{
	db_lp = db_line;
	db_last_lp = db_lp;
	db_endlp = db_line;
}

void
db_switch_input(const char *buffer, int	size)
{
	db_lp = buffer;
	db_last_lp = db_lp;
	db_endlp = buffer + size;
	db_look_char = 0;
	db_look_token = 0;
}

void
db_save_lex_context(register struct db_lex_context *lp)
{
	lp->l_ptr = db_lp;
	lp->l_eptr = db_endlp;
	lp->l_char = db_look_char;
	lp->l_token = db_look_token;
}

void
db_restore_lex_context(register struct db_lex_context *lp)
{
	db_lp = lp->l_ptr;
	db_last_lp = db_lp;
	db_endlp = lp->l_eptr;
	db_look_char = lp->l_char;
	db_look_token = lp->l_token;
}

int
db_read_char(void)
{
	int	c;

	if (db_look_char != 0) {
	    c = db_look_char;
	    db_look_char = 0;
	}
	else if (db_lp >= db_endlp)
	    c = -1;
	else 
	    c = *db_lp++;
	return (c);
}

void
db_unread_char(int c)
{
	db_look_char = c;
}

void
db_unread_token(int t)
{
	db_look_token = t;
}

int
db_read_token(void)
{
	int	t;

	if (db_look_token) {
	    t = db_look_token;
	    db_look_token = 0;
	}
	else {
	    db_last_lp = db_lp;
	    if (db_look_char)
		db_last_lp--;
	    t = db_lex();
	}
	return (t);
}

db_expr_t db_tok_number;
char	db_tok_string[TOK_STRING_SIZE];

db_expr_t db_radix = 16;

void
db_flush_lex(void)
{
	db_flush_line();
	db_look_char = 0;
	db_look_token = 0;
}

#define	DB_DISP_SKIP	40		/* number of chars to display skip */

void
db_skip_to_eol(void)
{
	register int skip;
	register int t;
	register int n;
	const char *p;

	t = db_read_token();
	p = db_last_lp;
	for (skip = 0; t != tEOL && t != tSEMI_COLON && t != tEOF; skip++)
	    t = db_read_token();
	if (t == tSEMI_COLON)
	    db_unread_token(t);
	if (skip != 0) {
	    while (p < db_last_lp && (*p == ' ' || *p == '\t'))
		p++;
	    db_printf("Warning: Skipped input data \"");
	    for (n = 0; n < DB_DISP_SKIP && p < db_last_lp; n++)
		db_printf("%c", *p++);
	    if (n >= DB_DISP_SKIP)
		db_printf("....");
	    db_printf("\"\n");
	}
}

int
db_lex(void)
{
	register char *cp;
	register int c;

	c = db_read_char();
	while (c <= ' ' || c > '~') {
	    if (c == '\n' || c == -1)
		return (tEOL);
	    c = db_read_char();
	}

	cp = db_tok_string;
	*cp++ = c;

	if (c >= '0' && c <= '9') {
	    /* number */
	    int	r, digit;

	    if (c > '0')
		r = db_radix;
	    else {
		c = db_read_char();
		if (c == 'O' || c == 'o')
		    r = 8;
		else if (c == 'T' || c == 't')
		    r = 10;
		else if (c == 'X' || c == 'x')
		    r = 16;
		else {
		    cp--;
		    r = db_radix;
		    db_unread_char(c);
		}
		c = db_read_char();
		*cp++ = c;
	    }
	    db_tok_number = 0;
	    for (;;) {
		if (c >= '0' && c <= ((r == 8) ? '7' : '9'))
		    digit = c - '0';
		else if (r == 16 && ((c >= 'A' && c <= 'F') ||
				     (c >= 'a' && c <= 'f'))) {
		    if (c >= 'a')
			digit = c - 'a' + 10;
		    else
			digit = c - 'A' + 10;
		}
		else
		    break;
		db_tok_number = db_tok_number * r + digit;
		c = db_read_char();
		if (cp < &db_tok_string[sizeof(db_tok_string)-1])
			*cp++ = c;
	    }
	    cp[-1] = 0;
	    if ((c >= '0' && c <= '9') ||
		(c >= 'A' && c <= 'Z') ||
		(c >= 'a' && c <= 'z') ||
		(c == '_'))
	    {
		db_printf("Bad character '%c' after number %s\n", 
				c, db_tok_string);
		db_error(0);
		db_flush_lex();
		return (tEOF);
	    }
	    db_unread_char(c);
	    return (tNUMBER);
	}
	if ((c >= 'A' && c <= 'Z') ||
	    (c >= 'a' && c <= 'z') ||
	    c == '_' || c == '\\' || c == ':')
	{
	    /* identifier */
	    if (c == '\\') {
		c = db_read_char();
		if (c == '\n' || c == -1)
		    db_error("Bad '\\' at the end of line\n");
	        cp[-1] = c;
	    }
	    while (1) {
		c = db_read_char();
		if ((c >= 'A' && c <= 'Z') ||
		    (c >= 'a' && c <= 'z') ||
		    (c >= '0' && c <= '9') ||
		    c == '_' || c == '\\' || c == ':' || c == '.')
		{
		    if (c == '\\') {
			c = db_read_char();
			if (c == '\n' || c == -1)
			    db_error("Bad '\\' at the end of line\n");
		    }
		    *cp++ = c;
		    if (cp == db_tok_string+sizeof(db_tok_string)) {
			db_error("String too long\n");
			db_flush_lex();
			return (tEOF);
		    }
		    continue;
		}
		else {
		    *cp = '\0';
		    break;
		}
	    }
	    db_unread_char(c);
	    return (tIDENT);
	}

	*cp = 0;
	switch (c) {
	    case '+':
		return (tPLUS);
	    case '-':
		return (tMINUS);
	    case '.':
		c = db_read_char();
		if (c == '.') {
		    *cp++ = c;
		    *cp = 0;
		    return (tDOTDOT);
		}
		db_unread_char(c);
		return (tDOT);
	    case '*':
		return (tSTAR);
	    case '/':
		return (tSLASH);
	    case '=':
		c = db_read_char();
		if (c == '=') {
		    *cp++ = c;
		    *cp = 0;
		    return(tLOG_EQ);
		}
		db_unread_char(c);
		return (tEQ);
	    case '%':
		return (tPCT);
	    case '#':
		return (tHASH);
	    case '(':
		return (tLPAREN);
	    case ')':
		return (tRPAREN);
	    case ',':
		return (tCOMMA);
	    case '\'':
		return (tQUOTE);
	    case '"':
		/* string */
		cp = db_tok_string;
		c = db_read_char();
		while (c != '"' && c > 0 && c != '\n') {
		    if (cp >= &db_tok_string[sizeof(db_tok_string)-1]) {
			db_error("Too long string\n");
			db_flush_lex();
			return (tEOF);
		    }
		    if (c == '\\') {
			c = db_read_char();
			switch(c) {
			case 'n':
			    c = '\n'; break;
			case 't':
			    c = '\t'; break;
			case '\\':
			case '"':
			    break;
			default:
			    db_printf("Bad escape sequence '\\%c'\n", c);
			    db_error(0);
			    db_flush_lex();
			    return (tEOF);
			}
		    }
		    *cp++ = c;
		    c = db_read_char();
		}
		*cp = 0;
		if (c != '"') {
		    db_error("Non terminated string constant\n");
		    db_flush_lex();
		    return (tEOF);
		}
		return (tSTRING);
	    case '$':
		return (tDOLLAR);
	    case '!':
		c = db_read_char();
		if (c == '=') {
		    *cp++ = c;
		    *cp = 0;
		    return(tLOG_NOT_EQ);
		}
		db_unread_char(c);
		return (tEXCL);
	    case '&':
		c = db_read_char();
		if (c == '&') {
		    *cp++ = c;
		    *cp = 0;
		    return(tLOG_AND);
		}
		db_unread_char(c);
		return(tBIT_AND);
	    case '|':
		c = db_read_char();
		if (c == '|') {
		    *cp++ = c;
		    *cp = 0;
		    return(tLOG_OR);
		}
		db_unread_char(c);
		return(tBIT_OR);
	    case '<':
		c = db_read_char();
		*cp++ = c;
		*cp = 0;
		if (c == '<')
		    return (tSHIFT_L);
		if (c == '=')
		    return (tLESS_EQ);
		cp[-1] = 0;
		db_unread_char(c);
		return(tLESS);
		break;
	    case '>':
		c = db_read_char();
		*cp++ = c;
		*cp = 0;
		if (c == '>')
		    return (tSHIFT_R);
		if (c == '=')
		    return (tGREATER_EQ);
		cp[-1] = 0;
		db_unread_char(c);
		return (tGREATER);
		break;
	    case ';':
		return (tSEMI_COLON);
	    case '?':
		return (tQUESTION);
	    case -1:
		strlcpy(db_tok_string, "<EOL>", TOK_STRING_SIZE);
		return (tEOF);
	}
	db_printf("Bad character '%c'\n", c);
	db_flush_lex();
	return (tEOF);
}
Commit	Line	Data
1c79356b	1	/*
2d21ac55	2	* Copyright (c) 2000-2006 Apple Computer, Inc. All rights reserved.
1c79356b	3	*
2d21ac55	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
1c79356b	5	*
2d21ac55 A	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. The rights granted to you under the License
	10	* may not be used to create, or enable the creation or redistribution of,
	11	* unlawful or unlicensed copies of an Apple operating system, or to
	12	* circumvent, violate, or enable the circumvention or violation of, any
	13	* terms of an Apple operating system software license agreement.
8f6c56a5	14	*
2d21ac55 A	15	* Please obtain a copy of the License at
	16	* http://www.opensource.apple.com/apsl/ and read it before using this file.
	17	*
	18	* The Original Code and all software distributed under the License are
	19	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
8f6c56a5 A	20	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
8f6c56a5 A	21	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
2d21ac55 A	22	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	23	* Please see the License for the specific language governing rights and
	24	* limitations under the License.
8f6c56a5	25	*
2d21ac55	26	* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
1c79356b A	27	*/
	28	/*
	29	* @OSF_COPYRIGHT@
	30	*/
	31	/*
	32	* HISTORY
	33	*
	34	* Revision 1.1.1.1 1998/09/22 21:05:48 wsanchez
	35	* Import of Mac OS X kernel (~semeria)
	36	*
	37	* Revision 1.1.1.1 1998/03/07 02:26:09 wsanchez
	38	* Import of OSF Mach kernel (~mburg)
	39	*
	40	* Revision 1.1.11.3 1996/01/09 19:15:49 devrcs
	41	* Change 'register foo' to 'register int foo'.
	42	* [1995/12/01 21:42:12 jfraser]
	43	*
	44	* Merged '64-bit safe' changes from DEC alpha port.
	45	* [1995/11/21 18:03:11 jfraser]
	46	*
	47	* Revision 1.1.11.2 1995/01/06 19:10:21 devrcs
	48	* mk6 CR668 - 1.3b26 merge
	49	* * Revision 1.1.4.6 1994/05/06 18:39:20 tmt
	50	* Merged osc1.3dec/shared with osc1.3b19
	51	* Merge Alpha changes into osc1.312b source code.
	52	* String protos.
	53	* 64bit cleanup.
	54	* Cleanup to quiet gcc warnings.
	55	* * End1.3merge
	56	* [1994/11/04 08:49:35 dwm]
	57	*
	58	* Revision 1.1.11.1 1994/09/23 01:19:59 ezf
	59	* change marker to not FREE
	60	* [1994/09/22 21:10:14 ezf]
	61	*
	62	* Revision 1.1.4.4 1993/08/11 20:37:55 elliston
	63	* Add ANSI Prototypes. CR #9523.
	64	* [1993/08/11 03:33:26 elliston]
	65	*
	66	* Revision 1.1.4.3 1993/07/27 18:27:38 elliston
	67	* Add ANSI prototypes. CR #9523.
	68	* [1993/07/27 18:12:13 elliston]
	69	*
	70	* Revision 1.1.4.2 1993/06/02 23:11:27 jeffc
	71	* Added to OSF/1 R1.3 from NMK15.0.
	72	* [1993/06/02 20:56:32 jeffc]
	73	*
	74	* Revision 1.1 1992/09/30 02:01:10 robert
	75	* Initial revision
	76	*
	77	* $EndLog$
	78	*/
	79	/* CMU_HIST */
	80	/*
	81	* Revision 2.5 91/10/09 16:00:20 af
	82	* Revision 2.4.3.1 91/10/05 13:06:25 jeffreyh
	83	* Added relational operator tokens and string constant etc.
	84	* Added input switching functions for macro and conditional command.
	85	* Moved skip_to_eol() from db_command.c and added db_last_lp to print
	86	* skipped input data as a warning message.
	87	* Added last input repetition support to db_read_line.
	88	* Changed db_lex() to always set db_tok_string for error message.
	89	* [91/08/29 tak]
	90	*
91	* Revision 2.4.3.1 91/10/05 13:06:25 jeffreyh
92	* Added relational operator tokens and string constant etc.
93	* Added input switching functions for macro and conditional command.
94	* Moved skip_to_eol() from db_command.c and added db_last_lp to print
95	* skipped input data as a warning message.
96	* Added last input repetition support to db_read_line.
97	* Changed db_lex() to always set db_tok_string for error message.
98	* [91/08/29 tak]
99	*
100	* Revision 2.4 91/05/14 15:34:23 mrt
101	* Correcting copyright
102	*
103	* Revision 2.3 91/02/05 17:06:36 mrt
104	* Changed to new Mach copyright
105	* [91/01/31 16:18:20 mrt]
106	*
107	* Revision 2.2 90/08/27 21:51:10 dbg
108	* Add 'dotdot' token.
109	* [90/08/22 dbg]
110	*
111	* Allow backslash to quote any character into an identifier.
112	* Allow colon in identifier for symbol table qualification.
113	* [90/08/16 dbg]
114	* Reduce lint.
115	* [90/08/07 dbg]
116	* Created.
117	* [90/07/25 dbg]
118	*
119	*/
120	/* CMU_ENDHIST */
121	/*
122	* Mach Operating System
123	* Copyright (c) 1991,1990 Carnegie Mellon University
124	* All Rights Reserved.
125	*
126	* Permission to use, copy, modify and distribute this software and its
127	* documentation is hereby granted, provided that both the copyright
128	* notice and this permission notice appear in all copies of the
129	* software, derivative works or modified versions, and any portions
130	* thereof, and that both notices appear in supporting documentation.
131	*
132	* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
133	* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
134	* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
135	*
136	* Carnegie Mellon requests users of this software to return to
137	*
138	* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
139	* School of Computer Science
140	* Carnegie Mellon University
141	* Pittsburgh PA 15213-3890
142	*
143	* any improvements or extensions that they make and grant Carnegie Mellon
144	* the rights to redistribute these changes.
145	*/
146	/*
147	*/
148	/*
149	* Author: David B. Golub, Carnegie Mellon University
150	* Date: 7/90
151	*/
152	/*
153	* Lexical analyzer.
154	*/
2d21ac55	155	#include <string.h> /* For strlcpy(), strlcmp(), strlen() */
1c79356b A	156	#include <ddb/db_lex.h>
	157	#include <ddb/db_command.h>
	158	#include <ddb/db_input.h>
	159	#include <ddb/db_output.h> /* For db_printf() */
	160
	161	char db_line[DB_LEX_LINE_SIZE];
	162	char db_last_line[DB_LEX_LINE_SIZE];
2d21ac55 A	163	const char db_lp, db_endlp;
2d21ac55 A	164	const char *db_last_lp;
1c79356b A	165	int db_look_char = 0;
	166	db_expr_t db_look_token = 0;
	167
	168
	169	/* Prototypes for functions local to this file. XXX -- should be static!
	170	*/
	171	void db_flush_line(void);
	172	void db_unread_char(int c);
	173
	174
	175	int
2d21ac55	176	db_read_line(const char *repeat_last)
1c79356b A	177	{
	178	int i;
	179
	180	i = db_readline(db_line, sizeof(db_line));
	181	if (i == 0)
	182	return (0); /* EOI */
	183	if (repeat_last) {
	184	if (strncmp(db_line, repeat_last, strlen(repeat_last)) == 0) {
2d21ac55	185	strlcpy(db_line, db_last_line, DB_LEX_LINE_SIZE);
1c79356b A	186	db_printf("%s", db_line);
	187	i = strlen(db_line);
	188	} else if (db_line[0] != '\n' && db_line[0] != 0)
2d21ac55	189	strlcpy(db_last_line, db_line, DB_LEX_LINE_SIZE);
1c79356b A	190	}
	191	db_lp = db_line;
	192	db_endlp = db_lp + i;
	193	db_last_lp = db_lp;
	194	db_look_char = 0;
	195	db_look_token = 0;
	196	return (i);
	197	}
	198
	199	void
	200	db_flush_line(void)
	201	{
	202	db_lp = db_line;
	203	db_last_lp = db_lp;
	204	db_endlp = db_line;
	205	}
	206
	207	void
2d21ac55	208	db_switch_input(const char *buffer, int size)
1c79356b A	209	{
	210	db_lp = buffer;
	211	db_last_lp = db_lp;
	212	db_endlp = buffer + size;
	213	db_look_char = 0;
	214	db_look_token = 0;
	215	}
	216
	217	void
	218	db_save_lex_context(register struct db_lex_context *lp)
	219	{
	220	lp->l_ptr = db_lp;
	221	lp->l_eptr = db_endlp;
	222	lp->l_char = db_look_char;
	223	lp->l_token = db_look_token;
	224	}
	225
	226	void
	227	db_restore_lex_context(register struct db_lex_context *lp)
	228	{
	229	db_lp = lp->l_ptr;
	230	db_last_lp = db_lp;
	231	db_endlp = lp->l_eptr;
	232	db_look_char = lp->l_char;
	233	db_look_token = lp->l_token;
	234	}
	235
	236	int
	237	db_read_char(void)
	238	{
	239	int c;
	240
	241	if (db_look_char != 0) {
	242	c = db_look_char;
	243	db_look_char = 0;
	244	}
	245	else if (db_lp >= db_endlp)
	246	c = -1;
	247	else
	248	c = *db_lp++;
	249	return (c);
	250	}
	251
	252	void
	253	db_unread_char(int c)
	254	{
	255	db_look_char = c;
	256	}
	257
	258	void
	259	db_unread_token(int t)
	260	{
	261	db_look_token = t;
	262	}
	263
	264	int
	265	db_read_token(void)
	266	{
	267	int t;
	268
	269	if (db_look_token) {
	270	t = db_look_token;
	271	db_look_token = 0;
	272	}
273	else {
274	db_last_lp = db_lp;
275	if (db_look_char)
276	db_last_lp--;
277	t = db_lex();
278	}
279	return (t);
280	}
281
282	db_expr_t db_tok_number;
283	char db_tok_string[TOK_STRING_SIZE];
284
285	db_expr_t db_radix = 16;
286
287	void
288	db_flush_lex(void)
289	{
290	db_flush_line();
291	db_look_char = 0;
292	db_look_token = 0;
293	}
294
295	#define DB_DISP_SKIP 40 /* number of chars to display skip */
296
297	void
298	db_skip_to_eol(void)
299	{
300	register int skip;
301	register int t;
302	register int n;
2d21ac55	303	const char *p;
1c79356b A	304
	305	t = db_read_token();
	306	p = db_last_lp;
	307	for (skip = 0; t != tEOL && t != tSEMI_COLON && t != tEOF; skip++)
	308	t = db_read_token();
	309	if (t == tSEMI_COLON)
	310	db_unread_token(t);
	311	if (skip != 0) {
	312	while (p < db_last_lp && (p == ' ' \|\| p == '\t'))
	313	p++;
	314	db_printf("Warning: Skipped input data \"");
	315	for (n = 0; n < DB_DISP_SKIP && p < db_last_lp; n++)
	316	db_printf("%c", *p++);
	317	if (n >= DB_DISP_SKIP)
	318	db_printf("....");
	319	db_printf("\"\n");
	320	}
	321	}
	322
	323	int
	324	db_lex(void)
	325	{
	326	register char *cp;
	327	register int c;
	328
	329	c = db_read_char();
	330	while (c <= ' ' \|\| c > '~') {
	331	if (c == '\n' \|\| c == -1)
	332	return (tEOL);
	333	c = db_read_char();
	334	}
	335
	336	cp = db_tok_string;
	337	*cp++ = c;
	338
	339	if (c >= '0' && c <= '9') {
	340	/* number */
	341	int r, digit;
	342
	343	if (c > '0')
	344	r = db_radix;
	345	else {
	346	c = db_read_char();
	347	if (c == 'O' \|\| c == 'o')
	348	r = 8;
	349	else if (c == 'T' \|\| c == 't')
	350	r = 10;
	351	else if (c == 'X' \|\| c == 'x')
	352	r = 16;
	353	else {
	354	cp--;
	355	r = db_radix;
	356	db_unread_char(c);
	357	}
	358	c = db_read_char();
	359	*cp++ = c;
	360	}
	361	db_tok_number = 0;
	362	for (;;) {
	363	if (c >= '0' && c <= ((r == 8) ? '7' : '9'))
	364	digit = c - '0';
	365	else if (r == 16 && ((c >= 'A' && c <= 'F') \|\|
	366	(c >= 'a' && c <= 'f'))) {
	367	if (c >= 'a')
368	digit = c - 'a' + 10;
369	else
370	digit = c - 'A' + 10;
371	}
372	else
373	break;
374	db_tok_number = db_tok_number * r + digit;
375	c = db_read_char();
376	if (cp < &db_tok_string[sizeof(db_tok_string)-1])
377	*cp++ = c;
378	}
379	cp[-1] = 0;
380	if ((c >= '0' && c <= '9') \|\|
381	(c >= 'A' && c <= 'Z') \|\|
382	(c >= 'a' && c <= 'z') \|\|
383	(c == '_'))
384	{
385	db_printf("Bad character '%c' after number %s\n",
386	c, db_tok_string);
387	db_error(0);
388	db_flush_lex();
389	return (tEOF);
390	}
391	db_unread_char(c);
392	return (tNUMBER);
393	}
394	if ((c >= 'A' && c <= 'Z') \|\|
395	(c >= 'a' && c <= 'z') \|\|
396	c == '_' \|\| c == '\\' \|\| c == ':')
397	{
398	/* identifier */
399	if (c == '\\') {
400	c = db_read_char();
401	if (c == '\n' \|\| c == -1)
402	db_error("Bad '\\' at the end of line\n");
403	cp[-1] = c;
404	}
405	while (1) {
406	c = db_read_char();
407	if ((c >= 'A' && c <= 'Z') \|\|
408	(c >= 'a' && c <= 'z') \|\|
409	(c >= '0' && c <= '9') \|\|
410	c == '_' \|\| c == '\\' \|\| c == ':' \|\| c == '.')
411	{
412	if (c == '\\') {
413	c = db_read_char();
414	if (c == '\n' \|\| c == -1)
415	db_error("Bad '\\' at the end of line\n");
416	}
417	*cp++ = c;
418	if (cp == db_tok_string+sizeof(db_tok_string)) {
419	db_error("String too long\n");
420	db_flush_lex();
421	return (tEOF);
422	}
423	continue;
424	}
425	else {
426	*cp = '\0';
427	break;
428	}
429	}
430	db_unread_char(c);
431	return (tIDENT);
432	}
433
434	*cp = 0;
435	switch (c) {
436	case '+':
437	return (tPLUS);
438	case '-':
439	return (tMINUS);
440	case '.':
441	c = db_read_char();
442	if (c == '.') {
443	*cp++ = c;
444	*cp = 0;
445	return (tDOTDOT);
446	}
447	db_unread_char(c);
448	return (tDOT);
449	case '*':
450	return (tSTAR);
451	case '/':
452	return (tSLASH);
453	case '=':
454	c = db_read_char();
455	if (c == '=') {
456	*cp++ = c;
457	*cp = 0;
458	return(tLOG_EQ);
459	}
460	db_unread_char(c);
461	return (tEQ);
462	case '%':
463	return (tPCT);
464	case '#':
465	return (tHASH);
466	case '(':
467	return (tLPAREN);
468	case ')':
469	return (tRPAREN);
470	case ',':
471	return (tCOMMA);
472	case '\'':
473	return (tQUOTE);
474	case '"':
475	/* string */
476	cp = db_tok_string;
477	c = db_read_char();
478	while (c != '"' && c > 0 && c != '\n') {
479	if (cp >= &db_tok_string[sizeof(db_tok_string)-1]) {
480	db_error("Too long string\n");
481	db_flush_lex();
482	return (tEOF);
483	}
484	if (c == '\\') {
485	c = db_read_char();
486	switch(c) {
487	case 'n':
488	c = '\n'; break;
489	case 't':
490	c = '\t'; break;
491	case '\\':
492	case '"':
493	break;
494	default:
495	db_printf("Bad escape sequence '\\%c'\n", c);
496	db_error(0);
497	db_flush_lex();
498	return (tEOF);
499	}
500	}
501	*cp++ = c;
502	c = db_read_char();
503	}
504	*cp = 0;
505	if (c != '"') {
506	db_error("Non terminated string constant\n");
507	db_flush_lex();
508	return (tEOF);
509	}
510	return (tSTRING);
511	case '$':
512	return (tDOLLAR);
513	case '!':
514	c = db_read_char();
515	if (c == '=') {
516	*cp++ = c;
517	*cp = 0;
518	return(tLOG_NOT_EQ);
519	}
520	db_unread_char(c);
521	return (tEXCL);
522	case '&':
523	c = db_read_char();
524	if (c == '&') {
525	*cp++ = c;
526	*cp = 0;
527	return(tLOG_AND);
528	}
529	db_unread_char(c);
530	return(tBIT_AND);
531	case '\|':
532	c = db_read_char();
533	if (c == '\|') {
534	*cp++ = c;
535	*cp = 0;
536	return(tLOG_OR);
537	}
538	db_unread_char(c);
539	return(tBIT_OR);
540	case '<':
541	c = db_read_char();
542	*cp++ = c;
543	*cp = 0;
544	if (c == '<')
545	return (tSHIFT_L);
546	if (c == '=')
547	return (tLESS_EQ);
548	cp[-1] = 0;
549	db_unread_char(c);
550	return(tLESS);
551	break;
552	case '>':
553	c = db_read_char();
554	*cp++ = c;
555	*cp = 0;
556	if (c == '>')
557	return (tSHIFT_R);
558	if (c == '=')
559	return (tGREATER_EQ);
560	cp[-1] = 0;
561	db_unread_char(c);
562	return (tGREATER);
563	break;
564	case ';':
565	return (tSEMI_COLON);
566	case '?':
567	return (tQUESTION);
568	case -1:
2d21ac55	569	strlcpy(db_tok_string, "<EOL>", TOK_STRING_SIZE);
1c79356b A	570	return (tEOF);
	571	}
	572	db_printf("Bad character '%c'\n", c);
	573	db_flush_lex();
	574	return (tEOF);
	575	}